So I've purchased a ticket for Japan! I fly from Buffalo to Osaka on September 24th. Yes, yes, very exciting, I know.

I have some questions perhaps one of you could answer for me. I will be purchasing a return ticket soon as it's a requirement for the working-holiday visa. The visa automatically grants one 6 months in Japan and can then be extended for another 6 months. Since I am hoping to be there for at least 10 months, I am wondering how likely it is that I'll be able to extend my visa? I assume it depends on my work status, housing situation and the like.
Especially since I would prefer to purchase a return ticket for 10+ months after arrival.